Cooling system, electric motor and wind-power electric generator set

ABSTRACT

The present disclosure relates to a cooling system, an electric motor and a wind-power electric generator set. The cooling system is applied to an electric motor; the electric motor includes a stator support and a rotor support, the stator support is dynamically sealingly connected to the rotor support to form ventilation chambers respectively arranged at two ends of the electric motor in an axial direction, first ventilation holes are formed at two ends of the stator support in the axial direction respectively, and the cooling system includes: a flow-confluence chamber, arranged in a circumferential direction of the stator support; an accommodating chamber, arranged in the circumferential direction of the stator support; a heat exchanger, arranged in the accommodating chamber or in the flow-confluence chamber; a circulating fan, arranged in the circumferential direction of the stator support and located at a side of the stator support in the axial direction.

CROSS REFERENCE TO RELATED APPLICATION

This application is a National Stage of International Application No.PCT/CN2020/078408, filed Mar. 9, 2020, which claims priority to and thebenefit of Chinese Patent Application No. 201910364164.5, filed Apr. 30,2019, the entireties of which are hereby incorporated herein byreference.

TECHNICAL FIELD

The present disclosure relates to a technical filed of cooling, andparticularly relates to a cooling system, an electric motor and awind-power electric generator set.

BACKGROUND

Wind power is one of the renewable energy technologies closest tocommercialization, and is the focus of renewable energy development. Aelectric motor in a wind-power electric generator set has the heat lossduring operation, in which the heat loss mainly includes: theelectromagnetic loss, that is, the Joule heat generated by the ohmicimpedance in a winding set, that is, the copper loss; the hysteresisloss, the eddy current loss and the like in an iron core, that is, theiron loss; and the inevitable stray loss; if the electric motor is apermanent magnet electric motor, it further includes the magnetic steelloss. Because of these losses cause, the electric motor releases a largeamount of heat when is working, and the heat will not only cause acertain impact on the electric motor itself and a insulation structureof the electric motor, which can lead to the shortened insulation lifeand even insulation failure, but also cause the output power of theelectric motor to continue to be reduced.

With the rapid development of an offshore wind-power electric generatorset, a unit generator capacity of the set continues to increase, whichdirectly leads to the losses of the wind-power electric generator setcontinuously increasing, and a cooling system of the electric motor willoccupy more space in a nacelle. For working conditions with heavysandstorms or harsh working environments, especially for marine salt fogenvironments, an air-to-air cooling system is likely to cause dustaccumulation in the electric generator and the cooling air volume of thesystem decreasing, resulting in the insufficient heat dissipation, andat the same time, it is more likely to cause damage and failure tocomponents and members, and reduce the life of the whole machine;adopting a water-cooling system, in order to ensure the temperaturelimitation of the winding set, the temperature rise requirements and thetemperature uniformity, it is bound to produce too many loops and jointsin the electric motor; at the same time, a compact flow channelincreases the resistance of the system and increases theself-consumption; considering the cooling of the ends and the rotor ofthe winding set, an air cooling system needs to be configuredindependently, resulting in a complicated structure of the coolingsystem and the reduced reliability.

SUMMARY

The object of the present disclosure is to provide a cooling system, anelectric motor and a wind-power electric generator set, and an overallstructure of the cooling system is simple and compact, and occupiessmaller space.

In one aspect, a cooling system applied to an electric motor is providedby the present disclosure; the electric motor includes a stator supportand a rotor support, the stator support is dynamically sealinglyconnected to the rotor support to form ventilation chambers respectivelyarranged at two ends of the electric motor in an axial direction, firstventilation holes are formed at two ends of the stator support in theaxial direction respectively, and the cooling system includes aflow-confluence chamber, arranged in a circumferential direction of thestator support; an accommodating chamber, arranged in thecircumferential direction of the stator support; in which theaccommodating chamber is located at an inner side of the flow-confluencechamber in a radial direction and communicates with the flow-confluencechamber, and the first ventilation holes are located outside theaccommodating chamber; a heat exchanger, arranged in the accommodatingchamber or the flow-confluence chamber; a circulating fan, arranged inthe circumferential direction of the stator support and located at aside of the stator support in the axial direction, wherein thecirculating fan has an air inlet and an air outlet; herein, aftercooling air flows out of the air outlet of the circulating fan, a partof the cooling air enters one end of the ventilation chamber which iscloser; the other part of the cooling air enters the other end of theventilation chamber through the first ventilation holes, which arerespectively formed at the two ends of the stator support in the axialdirection, the two parts of the cooling air flow over a heat-generatingmember in the electric motor, and then enters the air inlet of thecirculating fan via the flow-confluence chamber, the heat exchanger andthe accommodating chamber.

In another aspect, an electric motor is provided by the presentdisclosure, including any one of the cooling systems as described above.

In another aspect, a wind-power electric generator set is provided bythe present disclosure, including a nacelle, and the electric motor asdescribed above, in which the circulating fan of the cooling system ofthe electric motor is arranged at a side of the nacelle.

In the cooling system and the electric motor provided by the presentdisclosure, by arranging the flow-confluence chamber in thecircumferential direction of the stator support; arranging theaccommodating chamber in the circumferential direction of the statorsupport, arranging the heat exchanger in the accommodating chamber orthe flow-confluence chamber, arranging the circulating fan at the statorsupport in the axial direction, and forming the first ventilation holeslocated at an outer side of the accommodating chamber at two ends of thestator support in the axial direction respectively, it can be achievedthat the heat-generating member inside the electric motor can be cooledcyclically, and the overall structure of the cooling system can besimple and compact and can occupy smaller space. In addition, byadopting the electric motor, the wind-power electric generator setprovided by the present disclosure can effectively reduce the size ofthe nacelle, thereby reducing the overall machine cost and the overallmachine load, and improving the reliability and maintainability of thewind-power electric generator set.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure can be better understood from the followingdescription of the specific embodiments of the present disclosure inconjunction with the drawings; herein, by reading the following detaileddescription of the non-limiting embodiments with reference to thedrawings, other features, objects, and advantages of the presentdisclosure will become more apparent, and the same or similar referencesigns indicate the same or similar features.

FIG. 1 shows a schematic view of an overall layout structure of anelectric motor according to the embodiments of the present disclosure;

FIG. 2 shows a partial structural schematic view of a cooling system ofan electric motor according to the embodiments of the presentdisclosure;

FIG. 3 shows a partial structural schematic view of the cooling systemof the electric motor shown in FIG. 2 in an axial direction;

FIG. 4 shows a cross-sectional view of the cooling system of theelectric motor shown in the direction A-A in FIG. 3;

FIG. 5 shows a partial exploded structural schematic view of the coolingsystem shown in FIG. 2;

FIG. 6 shows a structural schematic view of a fixing support of thecooling system shown in FIG. 5;

FIG. 7 shows a structural schematic view of another fixing support ofthe cooling system shown in FIG. 5.

In the drawings:

-   -   1—main shaft; 1 a—stator winding set; 1 b—stator iron core; 1        c—air gap; 1 d—radial ventilation channel; 10—stator support;        101—accommodating chamber; 102—flow-confluence chamber;        103—isolation chamber; 11—first separating plate; 111—inspection        opening; 12—second separating plate; 13—ring-shaped plate;        14—fixing support; 141—first plate; 142—second plate; 143—third        plate; 144—mounting groove; 15—cover plate; 151—first opening;        152—second opening; 16—filter member; 17—first end plate;        18—second end plate; a—first ventilation hole; b—second        ventilation hole;    -   20—rotor support; 2 a—magnetic steel; 21—ventilation chamber;    -   30—heat exchanger; 31—first joint; 32—second joint;        40—circulating fan; 401—housing; 402—fan; 403—motor; 41—air        inlet; 42—air outlet; 43—air supplying pipe; 50—liquid supplying        pipe; 60—liquid returning pipe/air returning pipe;    -   100—electric motor; 300—nacelle.

DETAILED DESCRIPTION

The features and exemplary embodiments of various aspects of the presentdisclosure will be described in detail below. Many specific details aredisclosed in the following detailed description in order to fullyunderstand the present disclosure. However, it is obvious to thoseskilled in the art that the present disclosure can be implementedwithout some of these specific details. The following description of theembodiments is merely to provide a better understanding of the presentdisclosure by showing examples of the present disclosure. The presentdisclosure is by no means limited to any specific configurations andalgorithms proposed below, but covers any modification, replacement andimprovement of elements, member and algorithms without departing fromthe spirit of the present disclosure. In the drawings and the followingdescription, well-known structures and technologies are not shown inorder to avoid unnecessary obscurity of the present disclosure.

In order to better understand the present disclosure, a cooling system,an electric motor and a wind-power electric generator set in theembodiments of the present disclosure will be described in detail belowin conjunction with FIG. 1 to FIG. 7.

Referring to FIG. 1 and FIG. 2 together, the electric motor 100 providedby the embodiments of the present disclosure, includes the coolingsystem; the cooling system has a compact structure and occupies smallerspace.

The electric motor may have a structure of an outer rotor and an innerstator, or a structure of an outer stator and an inner rotor. The statoris fixed on a fixing shaft by a stator support 10, the rotor is fixed ona moving shaft by a rotor support 20, and the fixing shaft and themoving shaft are connected by a bearing and realize the relativerotation. The fixing shaft and the moving shaft together form a mainshaft 1 of the electric motor. In order to ease of description, theembodiment of the present disclosure takes the electric motor with thestructure of the outer rotor and the inner stator as an example fordescription.

The stator includes a stator winding set 1 a and a plurality of statoriron cores 1 b arranged to be spaced apart from one another in an axialdirection; each of radial ventilation channels 1 d is formed betweeneach two adjacent stator iron cores 1 b. Each of stator iron cores 1 bincludes a yoke portion and a tooth portion (not shown in the drawings)integrally formed with the yoke portion. The stator winding set 1 a iswound around the tooth portion, and the stator is fixed to the statorsupport 10 through the yoke portion. A magnetic steel 2 a is arranged onthe rotor support 20, and an air gap 1 c is formed between the rotor andthe stator in a radial direction. The stator winding set 1 a, the statoriron cores 1 b and the magnetic steel 2 a are all heat-generatingmembers, and the cooling system is used to cool the heat-generatingmembers.

Referring to FIG. 2 and FIG. 4 together, the cooling system applied tothe electric motor as described above is provided by the embodiments ofthe present disclosure; the electric motor includes the stator support10 and the rotor support 20, the stator support 10 is dynamicallysealingly connected to the rotor support 20 to form ventilation chambers21 respectively arranged at two ends of the electric motor in the axialdirection, and first ventilation holes a are respectively formed at twoends of the stator support in the axial direction.

The cooling system includes a flow-confluence chamber 102, anaccommodating chamber 101, a heat exchanger 30 and a circulating fan 40.

The flow-confluence chamber 102 is arranged in a circumferentialdirection of the stator support 10.

The accommodating chamber 101 is arranged in the circumferentialdirection of the stator support 10; the accommodating chamber 101 islocated at an inner side of the flow-confluence chamber 102 in theradial direction and communicates with the flow-confluence chamber 102;and the first ventilation holes a are located outside the accommodatingchamber 101.

The heat exchanger 30 is arranged in the accommodating chamber 101 or inthe flow-confluence chamber 102. The heat exchanger 30 may be anair-to-air heat exchanger or an air-to-liquid heat exchanger.Optionally, the heat exchanger 30 is, such as, but not limited to, aplate-fin type heat exchanger, a pipe-fin type heat exchanger or anarray pipe air-liquid type heat exchanger. A cooling medium in the heatexchanger 30 may be a liquid medium or a phase-changing medium. Thecooling medium in the heat exchanger 30 exchanges heat with an externalcooling system through a liquid supplying pipe 50 and a liquidreturning/air returning pipe 60 located at an outer side of the statorsupport 10, thereby circularly cooling the electric motor.

The circulating fan 40 is arranged in the circumferential direction ofthe stator support 10 and located at a side of the stator support 10 inthe axial direction, and the circulating fan has an air inlet 41 and anair outlet 42. Herein, after cooling air flows out of the air outlet 42of the circulating fan 40, a part of the cooling air enters one end ofthe ventilation chamber 21 which is closer; the other part of thecooling air enters the other end of the ventilation chamber 21 throughthe first ventilation holes a, which are respectively formed at the twoends of the stator support 10 in the axial direction, the two parts ofthe cooling air flow over a heat-generating member in the electricmotor, and enters the air inlet 41 of the circulating fan 40 via theflow-confluence chamber 102, the heat exchanger 30 and the accommodatingchamber 101.

Therefore, taking the heat exchanger 30 arranged in the accommodatingchamber 101 as an example, a cooling process of the cooling systemprovided by the embodiments of the present disclosure is as follows: thecooling air enters the circulating fan 40 from the heat exchanger 30through the air inlet 41, and directly enters an external environmentunder a negative pressure of the circulating fan 40, so that it canensure the uniformity of an inlet airflow. Herein, a part of the coolingair passes through the air outlet 42 and directly enters the ventilationchamber 21 at the near end; as shown by a solid arrow W1 in FIG. 3, thepart of cooling air cools an end of the stator winding set 1 a, and thenflows along the air gap 1 c, so that it can be achieved that a part ofthe magnetic steel 2 a, the rotor yoke and the stator winding set 1 a iscooled; the other part of the cooling air enters the ventilation chamber21 at the other end of the electric motor through the first ventilationholes a at the two ends of the stator support 10 in the axial direction;as shown by a solid arrow W2 in FIG. 3, the other part of the coolingair cools the other end of the stator winding set 1 a, and then flowsalong the air gap 1 c to cool the other part of the magnetic steel 2 a,the rotor yoke and the stator winding set 1 a.

As shown by a dotted arrow W3 in FIG. 3, two parts of the cooling airentering the air gap 1 c can cool the stator winding set 1 a and astator yoke through a plurality of radial ventilation channels 1 ddistributed to be spaced apart from one another in the axial directionof the stator; a temperature of the cooling air passing through theradial ventilation channels 1 d is increased, and the cooling air withthe high-temperature enters the accommodating chamber 101 via theflow-confluence chamber 102 and a second ventilation hole b under theaction of the circulating fan 40, so that the two parts of the coolingair entering the air gap 1 c can exchange heat with the heat exchanger30. The flow-confluence chamber 102 and the accommodating chamber 101forms an effective airflow organization sealing chamber in the electricmotor to establish a reasonable airflow organization and to realize theeffective heat dissipation of the stator winding set 1 a, the statoriron cores 1 b and the magnetic steel 2 a. The heat exchanger 30 isconnected to an external cooling system through the liquid supplyingpipe 50 and the liquid returning pipe/air returning pipe 60, so that thetemperature of the cooling air is decreased to form an airflow with arelatively low temperature, and then the cooling air enters the externalenvironment again under the action of the circulating fan 40 to performthe next cooling cycle of the airflow organization.

Since the circulating fan 40 is arranged in the axial direction of theelectric motor, the air outlet 42 is arranged toward one of theventilation chambers 21 at an end of the shaft of the electric motor toguide the airflow from the heat exchanger 30 to the ventilation chamber21; and the airflow from the heat exchanger 30 is guided into anotherventilation chamber 21 through the first ventilation holes a formed atthe two ends of the stator support 10 in the axial. By means of anorganic combination of the heat exchanger 30, the circulating fan 40 andthe stator support 10, only one air outlet 42 needs to be formed on thecirculating fan 40, so that the volume of the circulating fan 40 can bereduced.

In addition, the liquid supplying pipe 50 and the liquid returningpipe/gas returning pipe 60 of the heat exchanger 30 are located at anoutside of the accommodating chamber 101, so that it can furthersimplify an internal structure of the electric motor, and can make anoverall structure of the motor simpler, more compact, and occupy smallerspace.

In the cooling system provided by the embodiments of the presentdisclosure, the flow-confluence chamber 102 and the accommodatingchamber 101 communicating with the flow-confluence chamber 102 areformed in the circumferential direction of the stator support 10, andthe heat exchanger 30 is arranged in the flow-confluence chamber 102 orthe accommodating chamber 101, the circulating fan 40 is arranged in theaxial direction of the stator support 10, and the first ventilationholes a, which are located at an outer side of the accommodating chamber101, are respectively formed at two ends of the stator support in theaxial direction, so that it can be achieved that the heat-generatingmembers inside the electric motor can be cooled cyclically, and theoverall structure of the cooling system can be simple and compact andcan occupy smaller space.

The specific structure of the cooling system will be described infurther detail below in conjunction with the drawings.

Further referring to FIG. 1, in some embodiments, two or morecirculating fans 40 are distributed to be spaced apart from one anotherin the circumferential direction of the stator support 10, thus,compared to an integral circulating fan arranged in the axial directionof the stator support, the same heat dissipation effect can be achieved,and the overall structure of the electric motor can be simple andcompact and can occupy smaller space at the same time.

Optionally, two or more accommodating chambers 101 are distributed to bespaced apart from one another in the circumferential direction of thestator support 10 and correspond to the two or more circulating fans 40in a one-to-one correspondence, and the heat exchanger 30 is arranged ineach of the accommodating chambers 101. Optionally, the two or morecirculating fans 40 are evenly distributed in the circumferentialdirection of the stator support 10; correspondingly, the accommodatingchambers 101 and the circulating fans 40 are also evenly distributed inthe circumferential direction of the stator support 10.

Since the ventilation chambers 21 at the two ends of the electric motorin the axial direction have a large enough volume, they can serve as astatic pressure chamber, so that the ends of the stator winding set 1 ahave a uniform cooling effect, while ensuring the uniformity of theairflow entering the air gap 1 c in the axial direction; the cooling airentering the air gap 1 c flows along the air gap 1 c, and at the sametime flows through the stator winding set 1 a and the radial ventilationchannels 1 d of the stator iron cores 1 b into the flow-confluencechamber 102; the flow-confluence chamber 102 also has a large enoughvolume to serve as the static pressure chamber, thereby ensuring theuniformity of the airflow in an entire circumferential space, avoidingthe uneven airflow organization, and improving the uniformity of theheat dissipation of the cooling system.

Further referring to FIG. 4, the stator support 10 includes aring-shaped plate 13 extending in the axial direction; the ring-shapedplate 13 divides the stator support 10 into the flow-confluence chamber102 and the accommodating chamber 101 in the radial direction; thering-shaped plate 13 is provided with at least one second ventilationhole b in the circumferential direction; and the flow-confluence chamber102 communicates with the accommodating chamber 101 through the secondventilation hole b.

Further, the stator support 10 further includes a first end plate 17 anda second end plate 18 that extend in the radial direction and arearranged opposite to each other in the axial direction, and theflow-confluence chamber 102 extending through in the circumferentialdirection is formed by the first end plate 17, the second end plate 18and the ring-shaped plate 13.

The stator support 10 further includes a first separating plate 11 and asecond separating plate 12 that are located between the first end plate17 and the second end plate 18, extend in the radial direction, and arearranged coaxially; the first separating plate 11 is located on an innerside of the first end plate 17 in the radial direction, the secondseparating plate 12 is located on an inner side of the second end plate18 in the radial direction, and the accommodating chamber 101 is formedby the first separating plate, the second separating plate and thering-shaped plate 13.

The first ventilation holes a are arranged on the first separating plate11 and the second separating plate 12; optionally, the heat exchanger 30is arranged in the accommodating chamber 101; optionally, thecirculating fan 40 is arranged at an outer side of the first separatingplate 11 in the axial direction.

Further, the circulating fan 40 includes a housing 401, and furtherincludes a fan 402 and a motor 403 that are accommodated in the housing401. The motor 403 drives the fan 402 to rotate. The air inlet 41 andthe air outlet 42 are respectively arranged on the housing 401.

In addition, an air supplying pipe 43 extending toward the firstseparating plate 11 is arranged at the air inlet 41 of the circulatingfan 40. Optionally, the air supplying pipe 43 is the pipe with avariable diameter, so as to buffer the vibration impact of a negativepressure cooling air flow generated by the circulating fan 40 on theaccommodating chamber 101.

For a working condition with heavy wind and sand or harsh workingenvironment, in order to avoid insufficient heat dissipation of theelectric motor due to dust accumulation or damage and failure of acomponent, optionally, filter members are respectively arranged at thefirst ventilation holes a of the first separating plate 11 and thesecond separating plate 12.

Referring to FIG. 5 to FIG. 7 together, the cooling system furtherincludes at least one fixing support 14 distributed to be spaced apartfrom one another in the circumferential direction of the stator support10, the fixing support 14 is arranged between the first separating plate11 and the second separating plate 12, and the heat exchanger 30 isdetachably mounted on the fixing support 14.

The fixing support 14 includes a first plate 141 and a second plate 142that extend in the radial direction and are arranged opposite to eachother in the circumferential direction, and a third plate 143 connectingthe first plate 141 and the second plate 142 and extending in thecircumferential direction of the stator support 10; the first plate 141and the second plate 142 are provided with mounting grooves 144extending in the axial direction respectively, and the heat exchanger 30is detachably mounted on the fixing support 14 through the mountinggrooves 144 of the first plate 141 and the second plate 142.

As shown in FIG. 6, in some embodiments, the mounting grooves 144 arerespectively arranged at sides of the first plate 141 and the secondplate 142 facing to each other, and the heat exchanger 30 is insertedinto the mounting grooves 144 of the first plate 141 and the secondplate 142. At this time, the accommodating chamber 101 is formed by thering-shaped plate 13, the stator support 10, the fixing support 14 andthe main shaft 1 together; the accommodating chamber 101 forms theeffective airflow organization sealing chamber in the electric motor, sothat the phenomenon of the airflow short circuit can be avoided when thecooling air entering the accommodating chamber 101 through the secondventilation hole b performs the heat exchange with the heat exchanger30.

In addition, when two or more accommodating chambers 101 are arranged atthe stator support 10 in its own circumferential direction, two or morefixing support 14 are distributed to be spaced apart from one another inthe circumferential direction of the stator support 10, and an isolationchamber 103 is formed between each two adjacent accommodating chambers101 by the fixing support 14; in other words, on an inner side of thering-shaped plate 15 in the radial direction, the isolation chamber 103and the accommodating chamber 101 are alternately arranged at the statorsupport 10 in the circumferential direction.

Because the flow-confluence chamber 102 communicates with the airfloworganization of the heat exchanger 30 in each accommodating chamber 101by means of the second ventilation hole b formed in the circumferentialdirection of the ring-shaped plate 13, and the isolation chamber 103communicates with the ventilation chambers 21 at the two ends of theelectric motor in the axial direction through the first ventilationholes a on the first separating plate 11 and the second separating plate12, each isolation chamber 103 communicates with the airfloworganization of each heat exchanger 30. After any circulating fan 40fails, other circulating fans 40 can still pass airflow through the heatexchanger 30 corresponding to the failed circulating fan 40, so that theheat dissipation requirements of the stator winding set 1 a, the statoriron cores 1 b and the magnetic steel 2 a corresponding to the failedcirculating fan 40 can be taken into consideration at the same time, andthe reliability and the fault tolerance of the electric motor can beimproved.

As shown in FIG. 7, in some embodiments, the mounting grooves 144 arerespectively arranged on sides of the first plate 141 and the secondplate 142 facing away from each other, and the heat exchanger 30 isinserted into the mounting groove 144 of the first plate 141 of thefixing support 14 and the mounting groove 144 of the second plate 142 ofanother adjacent fixing support 14. At this time, the accommodatingchamber 101 is formed by the ring-shaped plate 13, the stator support10, the first plate 141 of the fixing support 14, the second plate 142of another adjacent fixing support 14 and the main shaft 1 together; theaccommodating chamber 101 forms the effective airflow organizationsealing chamber in the electric motor, so that the phenomenon of theairflow short circuit can be avoided when the cooling air entering theaccommodating chamber 101 through the second ventilation hole b performsthe heat exchange with the heat exchanger 30.

Further referring to FIG. 5, an inspection opening 111 allowing the heatexchanger 30 to pass through is formed on the first separating plate 11,and the first separating plate 11 is sealingly covered at the inspectionopening 111 by a cover plate 15. For example, a sealing ring or the likeis arranged between the cover plate 15 and the inspection opening 111.

A first joint 31 and a second joint 32 are arranged on the heatexchanger 30; a first opening 151 and a second opening 152 are formed onthe cover plate 15; the first joint 31 extends out of the first opening151 and is connected to the liquid supplying pipe 50; the second joint32 extends out of the second opening 152 and is connected to the liquidreturning pipe/air returning pipe 60.

Therefore, on one hand, the fixing support 14 can be used as areinforcing rib of the stator support 10, which can improve thestructural strength and the rigidity of the stator support 10; on theother hand, the heat exchanger 30 is detachably inserted into themounting grooves 144, and the corresponding inspection opening 111 isformed on the first separating plate 11; when replacing or repairing theheat exchanger 30, it is only necessary to disassemble the cover plate15 and pull the heat exchanger 30 in the axial direction to quicklycomplete the replacement work from the inspection opening 111, so thatthe replacement efficiency can be improved.

Since the circulating fan 40 is arranged at the side of the statorsupport 10 in the axial direction, when the circulating fan 40 needs tobe replaced, the circulating fan 40 can be directly removed from the airsupplying pipe 43 without disassembling other components, so that themaintainability of the electric motor can be improved.

It should be noted that, although the cooling system has been describedabove to take the electric motor having the structure of the outer rotorand the inner stator as an example for the convenience of description,it should be understood that, according to the exemplary embodiments ofthe present disclosure, the working principle of the cooling system asdescribed above can also be applied to the electric motor having thestructure of outer stator and inner rotor, and the corresponding statorsupport 10 and rotor support 20 can be adapted to be modified.

In addition, a wind-power electric generator set is further provided bythe embodiments of the present disclosure, including a nacelle 300, andthe electric motor as described above, in which the circulating fan 40of the cooling system of the electric motor is arranged on a side of thenacelle 300, so that it is convenient for mounting, maintenance andreplacement in later.

The wind-power electric generator set provided by the embodiments of thepresent disclosure adopts the electric motor as described above, so thatit can effectively reduce the size of the nacelle 300, thereby reducingthe cost of the overall machine and the load of the overall machine, andimproving the reliability and the maintainability of the wind-powerelectric generator set.

In addition, the electric motor according to the exemplary embodimentdescribed above can be applied to various devices that need to beprovided with the electric motor, such as but not limited to thewind-power electric generator set.

Those skilled in the art should understand that the above-mentionedembodiments are all illustrative and not limited. Different technicalfeatures appearing in different embodiments can be combined to achievebeneficial effects. Those skilled in the art should be able tounderstand and implement other modified embodiments of the disclosedembodiments on the basis of studying the drawings, description, andclaims. In the claims, the term “comprising” does not exclude othermeans or steps; when an article is not modified with a quantitativeword, it is intended to include one/kind or multiple/kind of articles,and can be used interchangeably with “one/kind or multiple/kind ofarticles; the terms “first” and “second” are used to denote names ratherthan to indicate any specific order. Any reference signs in the claimsshould not be construed as limiting the scope of protection. Thefunctions of multiple parts appearing in the claims can be implementedby a single hardware or software module. The appearance of certaintechnical features in different dependent claims does not mean thatthese technical features cannot be combined to achieve beneficialeffects.

1. A cooling system, applied to an electric motor, wherein the electricmotor comprises a stator support and a rotor support, the stator supportis dynamically sealingly connected to the rotor support to formventilation chambers, the ventilation chambers are respectively arrangedat two ends of the electric motor in an axial direction, firstventilation holes are formed at two ends of the stator support in theaxial direction respectively, and the cooling system comprises aflow-confluence chamber, arranged in a circumferential direction of thestator support; an accommodating chamber, arranged in thecircumferential direction of the stator support; wherein theaccommodating chamber is located at an inner side of the flow-confluencechamber in a radial direction and communicates with the flow-confluencechamber, and the first ventilation holes are located outside theaccommodating chamber; a heat exchanger, arranged in the accommodatingchamber or in the flow-confluence chamber; a circulating fan, arrangedin the circumferential direction of the stator support and located at aside of the stator support in the axial direction, wherein thecirculating fan has an air inlet and an air outlet; wherein aftercooling air flows out of the air outlet of the circulating fan, a partof the cooling air enters one end of the ventilation chamber which iscloser; the other part of the cooling air enters the other end of theventilation chamber through the first ventilation holes, which arerespectively formed at the two ends of the stator support in the axialdirection, the two part of the cooling air flow over a heat-generatingmember in the electric motor, and then enters the air inlet of thecirculating fan via the flow-confluence chamber, the heat exchanger andthe accommodating chamber.
 2. The cooling system according to claim 1,wherein the stator support comprises a ring-shaped plate extending inthe axial direction; the stator support comprises the flow-confluencechamber and the accommodating chamber in the radial direction, and theflow-confluence chamber is connected with the accommodating chamber bythe ring-shaped plate; the ring-shaped plate is provided with at leastone second ventilation hole in the circumferential direction; and theflow-confluence chamber communicates with the accommodating chamberthrough the second ventilation hole.
 3. The cooling system according toclaim 2, wherein the stator support further comprises a first end plateand a second end plate that extend in the radial direction and arearranged opposite to each other in the axial direction, and theflow-confluence chamber extending through in the circumferentialdirection is formed by the first end plate, the second end plate and thering-shaped plate.
 4. The cooling system according to claim 3, whereinthe stator support further comprises a first separating plate and asecond separating plate that are located between the first end plate andthe second end plate, extend in the radial direction, and are arrangedcoaxially; the first separating plate and the second separating plateare respectively located on an inner side of the first end plate in theradial direction and an inner side of the second end plate in the radialdirection, and the accommodating chamber is formed by the firstseparating plate, the second separating plate and the ring-shaped plate.5. The cooling system according to claim 4, wherein the firstventilation holes are arranged at the first separating plate and thesecond separating plate, and/or the heat exchanger is arranged in theaccommodating chamber, and the circulating fan is arranged on an outerside of the first separating plate in the axial direction.
 6. Thecooling system according to claim 4, wherein the cooling system furthercomprises at least one fixing support distributed to be spaced apartfrom one another in the circumferential direction of the stator support,the fixing support is arranged between the first separating plate andthe second separating plate, and the heat exchanger is detachablymounted on the fixing support.
 7. The cooling system according to claim6, wherein the fixing support comprises a first plate and a second platethat extend in the radial direction of the stator support and arearranged opposite to each other in the circumferential direction of thestator support, and a third plate connecting the first plate and thesecond plate and extending in the circumferential direction of thestator support; the first plate and the second plate are provided withmounting grooves extending in the axial direction respectively, and theheat exchanger is detachably mounted on the fixing support through themounting grooves of the first plate and the second plate.
 8. The coolingsystem according to claim 7, wherein the mounting grooves arerespectively arranged at sides of the first plate and the second platefacing to each other, and the heat exchanger is inserted into themounting grooves of the first plate and the second plate.
 9. The coolingsystem according to claim 7, wherein the mounting grooves arerespectively arranged at sides of the first plate and the second platefacing away from each other, the heat exchanger is inserted into themounting groove of the first plate of the fixing support, and the heatexchanger (30) is further inserted into the mounting groove of thesecond plate of another adjacent fixing support.
 10. The cooling systemaccording to claim 6, wherein the cooling system comprises two or moreaccommodating chambers, an isolation chamber is formed by the fixingsupport between each two adjacent accommodating chambers, and theisolation chamber communicates with the first ventilation holes.
 11. Thecooling system according to claim 4, wherein filter members arerespectively arranged at the first ventilation holes on the firstseparating plate and the second separating plate.
 12. The cooling systemaccording to claim 4, wherein an inspection opening allowing the heatexchanger to pass through is formed on the first separating plate, andthe first separating plate is sealingly covered at the inspectionopening by a cover plate.
 13. The cooling system according to claim 1,wherein two or more circulating fans are distributed to be spaced apartfrom one another in the circumferential direction of the stator support;two or more accommodating chambers are distributed to be spaced apartfrom one another in the circumferential direction of the stator support,and correspond to the two or more circulating fans in a one-to-onecorrespondence, and the heat exchanger is arranged in each of theaccommodating chambers.
 14. An electric motor, comprising the coolingsystem according to claim
 1. 15. A wind-power electric generator set,comprising a nacelle, and the electric motor according to claim 14,wherein the circulating fan of the cooling system of the electric motoris arranged at a side of the nacelle.